Finn the Assassin Prince
by AngryBandit59
Summary: After a successful mission, the Assassin King finds a human baby and decides to take him under his wing...
1. Heir

**I know, I have another 50 stories to finish. But whenever I have an idea, I have to put it out there, you know? Or else, it'll shrivel away and I'll forget about it.**

* * *

The Assassin King walked through the forest, red cape flapping behind him, deep in thought. He had just assassinated the Mountain King, and he noticed something. He was getting old. He had been nearly spotted more than a few times by the Mountain Guards, but back in his prime he would have slit every throat in the whole castle without so much as an unsure glance at his vantage point. He was used to be shadow of death, and by all means he still was, but the white hairs in his orange mane and wrinkles in his dark gray skin would tell him otherwise.

He sighed. He just needed a walk to help clear his mind, though the two yellow dogs he ran into and killed a few minutes ago were just delightful. The screams of the female after he decapitated the male... sweeter than any wine.

Then the Assassin King heard crying. The crying of an infant, defiantly an odd sound in this area of the mountains.

Deciding to investigate further, the Monarch traveled further down the path, towards the crying.

He turned around the corner of the mountain and found a young baby boy with a bear hat wrapped up in a blanket. He gently picked up the baby, examining it.

He took off the bear hat, the babies blond hair spilling out. Assassin King gasped a bit, "A human? I thought they were extinct..."

As the baby started calming down as the Assassin began awkwardly rocking him back in forth in his arms, he noticed a piece of paper in the boy's blanket. He picked it up and read the hastily written note.

_His name is Finn. I'm so close to death... I can't take care of him anymore... please, take good care of him._

The Assassin King discarded the bear hat on the path and lifted Finn in the air, his chubby little legs kicking into the air.

The monarch smiled to himself. '_I may not be able to live forever... but you will be my legacy, Finn. I'll personally train you myself and you'll will take my place as the world's greatest Assassin.'_

* * *

**Should I keep this a oneshot? If I continue it, which girl should Finn get together with? **


	2. Rules

From an early age, Finn was trained to be a silent, killing machine: a deathly phantom, able to kill any target while remaining unseen and unheard. He was a master of countless weapon styles and martial arts.

There were three things he knew by heart: the three rules that all members of the Guild of Assassins must abide by. He lived by those rules.

First rule: Never leave your target alive. Failure to kill your target by deadline or showing mercy was strictly looked down upon, and was met by sever punishment.

Second rule: Keep stealthy. The GOA was a guild of assassin's, not slashers. You could kill as many people as you wanted (some missions even called for mass death), but you can't just go barging in, guns blazing.

Third rule: Never disobey orders from superiors. Refusal to accept a mission or back sassing was intolerable.

Breaking any of these three rules would be met by the Guild's single punishment: death.

Right now, Finn was on the prowl for someone who had broken the first rule. His name was Caro, a green, lanky man who had mastered the ways of the ninja.

He had refused to kill his target, the Breakfast Princess. How weak.

Caro had fled into a forest, and Finn was jumping from branch to branch in the cloudy night, catching up to the green ninja.

Finn wore a white long coat with a hood, which he always kept pulled up over his golden locks. He kept many poisons, explosives, and throwable and retractable weapons in the pockets of that long coat.

He also wore brown boots that went up to his calf's, black trousers, and a dark blue shirt with light, protective padding underneath. He also had his father's sword, Lifetaker, strapped across his back in a black sheath.

Finn hopped on yet another branch, then suddenly heard a hissing noise.

'_Explosives!'_

Finn jumped off the branch just in time, being blown back by the bomb planted on the tree detonnating.

Finn landed on the ground off the forest, relativity unharmed. He sat up and heard a voice behind him, "So, the old man sent his precious little human boy to kill me, huh?"

Finn spun around to see Caro standing there, arms folded. He wore a full body, purple ninja suit, and had an ancient katana slung across his back.

Finn narrowed his eyes at the ninja, "Don't get cocky, Caro... we both know I'm the better fighter here. Give it up, and I'll make it quick."

Caro suddenly spun around and jumped through some shrubs, running through the forest. Finn chased after him, right behind the ninja.

After about a minute of sprinting, Finn found himself in a clearing filled to the brim with wild flowers, Caro the Ninja standing a few yards away from him.

"We have plenty of room to play here, Finn. Hope you're not winded from that little fun run."

Finn smirked, drawing the sword Lifetaker from his back, "Didn't even break a sweat."

Caro quickly drew his blade and swung it at Finn, who blocked with Lifetaker.

Caro's katana was a silvery blade with a dragon-designed handle, while life taker had a razor-sharp blade with a lion design for the cross guard, making it look like the blade was jutting out of the lion's mouth.

Their blades danced off of each other, shooting off sparks into the pale moonlight. Both assassin's swung their swords around with machine-like efficiency, and the loud clanging could be heard throughout the forest.

Finn swung his sword above his head, catching Caro of guard. He slashed at the ninja's arm, leaving a deep wound.

Caro stumbled backwards, grasping at his injury. Finn smiled to himself, "Caro, give it up. You know you can't win."

Caro frowned, the grimace being visible through his mask. He reached into his belt and tossed several shruiken stars at Finn, who responded by pulling out several throwing knives at him.

The knifes all crashed into the stars, but one slipped by and hit Caro dead center in his forehead, causing the ninja to fall backwards, crushing many wild flowers below him.

Finn walked over to his deceased, ex-comrade, pulling the knife out of his forehead and wiping the blood off, tucking it back into his long coat.

Finn then realized something. He had never seen the ninja without his mask. He yanked it off, revealing his face.

His face was green, and he looked decidedly beetle-like; large, round eyes and a small little mouth.

Finn stared into those round, dead eyes, trying to find the reason why he had showed mercy. He knew Caro. He was strong.

Finn simply spat into the ground, and pried the sword out of the dead ninja's hand.

Finn sheathed the katana, slinging it to his hip. He turned, looking back at Caro's corpse one last time, "Caro, you've always talked about honor. I know you're sword belonged to your ancestors, why would you shame them like this?"

Finn didn't expect an answer.

"Don't worry, friend. I'll bring your honor back by taking the lives of those you failed to kill with this sword."


	3. Love?

Finn landed outside of the Breakfeast Princesses window seal, silently opening the window and creeping into the darkness.

"Are... are you Caro's friend?" he heard a choked up, female voice ask him from across the room.

The light switch was flipped on, and standing there was the Breakfeast Princess, bacon-grease tears running down her cheeks.

Finn remained stoic, "Used to be. I had to take him out when he refused to kill you."

She looked like she was getting dizzy. She put her hand on the wall and sunk down, her face in her right hand, sobbing.

Finn walked over to her, katana drawn. He held it to her neck, "So, why didn't Caro kill you?"

She continued sobbing, "We were in love... he wasn't completely cold-hearted like you! I... I can't live without him... just kill me if you want..."

Finn remained stoic. He swirled his katana around and chopped the princess in two, her severed torso falling to the floor, bleeding out orange juice. She looked at him through beady, tear stained eyes as her life slowly slipped away.

Love. How foolish. He would never understand it, nor did he want to.

He jumped out the window, and made his way back to the Guild's secret base.

* * *

Finn walked through the halls of the Assassin's Guild, on his way to report back to the Assassin King, his adoptive father.

"Hey, Finn. Where have you been?"

Finn looked to see his small comrade', Me-Mow, sitting atop his right shoulder.

"I had to go kill Breakfeast Princess after I killed Caro." he said.

Me-Mow looked down to the human's side, where an ancient japenese blade was slung, "Hey, isn't that Caro's katana?"

Finn looked forward, approaching a large set of double doors with the GOA's symbol engraved in them that marked his adoptive father's throne room, "Yeah. It's a fine blade, and it would be a shame to let it just sit in a plain and rust, you know?"

Me-Mow smiled, "Yeah, I guess. So, I'll just let you talk your dad... wanna meet at the mess-hall later?"

Finn smiled as the little cat jumped off his shoulder, "Sure. Later, Me-Mow."

As the little cat scampered off, Finn sighed and pushed open the doors, thinking back to what Breakfeast Princess had said one last time.


	4. Jake

After making his way through the trap filled dungeon, Finn landed in front of the dog, scrutinizing him.

Jake, was his name. He had the power to stretch his body to any shape or size, and he was wielding a demon-blood sword.

He had already taken out 4 of the Guild's operatives, and Finn was sent to put a stop to it.

The dog brandished his sword at the young assassin, "So... another piece of assassin trash. What, did the Guild send you to kill me?"

Finn drew Lifetaker, pointing at Jake, "Yes, they did. Before we start, why are you doing this? Was it because the Assassin King killed your parents?"

Jake growled, "Not just that... I could understand how anyone could kill another for money... but just for fun...? You assassins are the worst kind of garbage, and after I'm through with you, I'll demolish your guild!"

Finn smirked, "I'd like to see you try, mutt."

Jake stretched his arm out, stabbing at Finn. Finn rolled out of the way, quickly getting back onto his feet. Finn slashed his sword out, but Jake managed to block it with his own blade. Jake began swinging his sword around wildly, apparently not well-trained in the art of blades.

Finn easily disarmed the dog, then grabbed his wrist. Finn slammed the dog against the ground, then threw him against the nearest wall. Jake quickly turned into a ball and rolled at the assassin, but Finn ran right at him, and at the last second, jumped on top of the dog, doing a handstand atop of the rolling animal and placing a small item before jumping off.

Jake unrolled himself, raising his enlarged fists, "That all you got?!"

Finn smirked, lifting up a small detonator. Jake gasped in surprise, twisting around to see the c4 stuck to his back a second too late.

With a light chuckle, Finn pressed the button, blowing the dog into bloody chunks.

Finn laughed, picking up the dog's demon-blood sword as a prize. That's when he noticed a smoking, bloody pendant lay out in front of him, apparently being blown off the dog's body.

Finn opened it up, seeing a photo of Jake stretching his arms around a rainicorn and 5 hybrids of dog and rainicorn.

Finn chuckled, shaking his head from side to side. All that talk about love, and yet he was so easy to lay his life on the line?

"Never will understand that 'love' garbage, and I'm pretty sure I don't want to..."

* * *

Finn walked into his father's throne room, bowing down to him, "I've completed my mission, father..."

The Assassin King smirked, "Excellent. Now, I have a new mission for you..."

He tossed his adoptive son a file, which the young killer caught with ease. He opened it up, seeing several file photos and public records focusing on a Vampire girl with flowing, ebony hair.

Finn stood, "Who hired me for this...?"

"It was I," said a well-dressed Peppermint, stepping out from the corner of the room.

Finn smiled, tucking the file into his long-coat, "Consider it done..."


	5. Ashes to Ashes

Finn landed on a tree branch, creeping into the large-tree house in from boat that acted as a balcony.

The young assassin peaked downstairs and silently cursed under his breath.

Ash, the Wizard, was there. Assassins and Wizards didn't have the best track record together, due to a huge drug dealing plot that went awry 134 years prior, in which both parties had their own roles, and blamed the other side when it failed.

Ash was a powerful and well respected Wizard. Finn could have easily killed the Vampire, but tossing that spell-caster into the mix made things a lot more complicated.

Finn lifted his fingers up to his codec, "Mission control? This is Finn."

"'Sup, Finn?" said Me-Mow from the other line.

Finn raised an eyebrow, "Me-Mow...? Since when do you do mission control?"

"Meh. Needed some extra cash, and they were fresh out of all the field jobs. So, what's the problem?"

Finn saw his primary target, Marceline, give Ash a sandwich, which he hastily accepted, and said something along the lines of, 'Took you long enough.'

"Ash is here..."

"You mean the wizard...? Hold on a sec, lemme check the files..."

Finn heard scampering and clicking, most likely the small cat running over the key-board, "'Kay... says here on Ash's records that he did in fact date Marceline at some point a few hundred years ago..."

Finn snorted, "Well, looks like they're back together... so, what should I do? I highly doubt I could kill the bitch without her boy-toy noticing... and if I kill him, it could break the wizards and assassins peace agreement..."

"Don't worry about that, just knock him off." Finn heard his father say on a third-line.

Finn gasped a bit, "Father? When did you..."

"I was standing behind Me-Mow the whole time... just go through with it. That flimsy little peace agreement wouldn't have lasted much longer anyway."

"Right. Over and out," said Finn, clicking his codex off. He rolled into the tree house, landing silently behind a table.

Ash finished his sandwich, setting down the plate and picking a small piece of ham out of his teeth. He peaked up at Marceline, "Not bad. Could still use some work, though."

Marceline smiled sweetly, "Thanks, Ashy."

Ash slapped her ass, causing the assassin peeping on them to shake his head from side-to-side. It was clear from the first few moments that Finn saw that he was using her for sex and food. The woman was 1000 years old... did she really not see that? Did she believe in the illusion of love, even as flimsy of an illusion as this?

"Come on, I'm horny." he said, grabbing her breast roughly. Finn pinched his nose, realizing he'd probably have to expose himself now.

Finn flipped from his hiding place, landing in front of the startled wizard and vamp, "Let's make this quick, wizard. Don't try and resist. It'll be less painful that way."

Ash growled, roughly tossing his girlfriend to the corner of the room, where she stayed sitting down , "Stay out of this, cunt. I can take this putrid fuckin' assassin all by myse-"

Ash was interrupted when Finn planted his fist directly into the wizard's face, breaking his nose. Ash reared back, clutching his injury and screaming in pain.

Ash uncovered his bloody face, gritting his teeth, "Why- why you- I'm going to kill you... nice and slowl-"

The wizard was interrupted yet again when Finn kicked him in the temple, sending him to the floor with a migraine.

Finn frowned as he looked down at the gray-skinned wizard, "You might do a little better if you'd stop flapping your gums and actually throw a punch."

Ash quickly scrambled to his feet, pulling out a wand, "DIE, YOU PIECE OF SHIT!"

He fired out a ball of compressed darkness. Finn smiled as he pulled out his new, crimson blade, deflecting it back at the wizard. Ash's eyes widened, and at the last second, he put up a ward, stopping his own attack from hitting him.

Ash put the ward down, "Not bad, for a mortal..."

Finn smirked, "Hey, you shouldn't look down on mortals. Especially ones that are kicking your ass."

Ash growled, "Why... you..."

The jerk-wizard's wand began cracking with lightning, "Lets see you dodge this!"

He pointed it at Finn and shot a small bolt of electricity, but Finn strafed out of the way. Ash growled and began firing off dozens off them, but Finn dodged each and every one of them.

Ash began huffing with fear, "Ho-how were you able to dodge all of my attacks?!"

Finn remained stoic, "Simple. Your aim is shit."

Ash began huffing with mix of rage, hate, and fear. "I! WILL! NOT! BE! MADE! A! FOOL! OF! BY! A MORTAL!" he screamed at the top of his lungs, punctuating each word, and grinding his teeth together.

Finn sighed, "Lets just get this over with..."

Ash shouted in rage, the wand he had sold Hambo for snapping under his grip. He tossed it to the side, and placed his hands out in front of him, a purple mass of energy charging in his palms.

He laughed like a madman, while his girlfriend sat in the corner of the room, watching with fear. Finn raised an eyebrow, "So, just gonna leave yourself open like that? Sure, why not? Lets just see what your super-special-platinum-chocolate coated attack is."

Ash laughed madly, the veins along his arms starting to throb, "I'M PUTTING ALL MY MANA INTO THIS SPELL, ASSHOLE!"

With a loud shout, the purple energy in his hands formed a ball, and Ash pointed it at Finn, "SUCK ON THIS, BITCH!"

Finn snorted and ducked under the flying purple ball as it flew at him, burning a hole in the treehouse and creating a decent-sized explosion in the distance.

Ash fell to his ass, Finn standing up and slowly walking towards him.

"So, put all your mana into one attack that can be easily read and dodged... quite cunning. Where did you learn magic, the back of a cereal box...?"

Ash got up, shaking with fear, "I- You... DON'T YOU DARE MOCK ME!"

He threw a fist at Finn, only for the assassin to catch it mid-swing, and slowly began breaking it.

Ash barley held back his tears of frustration, pain, and anger. He looked back at his girlfriend, who was still siting in the corner, "MARCELINE! GET YOUR BIMBO ASS OVER HERE AND HELP ME, YOU DUMB CUNT!"

Finn snapped Ash's wrist, making him cry out in pain, and drop to his knees. Marceline charged at Finn, only for the assassin to throw a small bag of garlic powder at her, causing her to fall down to the ground and choke to death. Garlic powder was basically nerve gas to Vampires.

Ash began crying, "Oh shit, oh shit... man, I'm sorry, PLEASE DON'T KILL ME!"

Finn slapped him across the face, "Get a hold of yourself, pussy, and give me one good reason I should spare you."

Ash put on a cheesy, fake grin, "My parents are loaded, brother! And I could hook you up with some of the finest bitches and drugs on the market!"

"I don't give a shit about money, I can get my own girls, and if these drugs make me flail around like an angry chimp who just got into his masters spell books like you, then I don't want them anywhere near me."

Ash tried to plead some more, but Finn shoved a grenade into his mouth, pulling the pin and jumping out of the way.

Ash's upper torso was blown to tiny pieces. Finn smirked, clicking his codex, "Finn here. Targets terminated."

"Great work as usual, Finn. Come on back to base."

Finn jumped out of the house, not noticing Marceline's fingers twitching...

* * *

**THAT'S WHAT YOU GET FOR ACTING THE** **MICKEY, ASH. Seriously, that was fun writing. I wish that there was a comic of AT where Finn just put the beat down on Ash, before he started crying like a little bitch and begging for his life, only for Finn to kill him in some gory, over-the-top way. Anyway, I'll explain why Ash and Marcy where back together and why she was so submissive in the next chapter.**


End file.
